Biodegradation of different organic solid waste by using epigeic earthworms

The main aim of this study for the reuse of organic wastes by vermicomposting method. A vermicomposting method is a recognised environmentally safe technology for waste reuse. It has a sustainable solid waste management. explosive growth of human population and technological advances has produced enormous quantities of solid wastes, the management of which has become a problem of global concern. Earthworms, by their peculiar food, feeding and burrowing habits are considered as the most efficient converters of wastes. India, being an agricultural country produces huge quantities of agricultural wastes, which can be converted into vermicompost, a nutrient rich bio fertilizer and soil conditioner. In the present study, an attempt has been made to explore the possibility of using earthworms for converting three different leaf litters – Vegetable wastes, and plant leaf litters into vermicompost. Three epigeic earthwormswell established as efficient bio convertors, P. excavatus, E. fetida and were used in this study.


INTRODUCTION
The biological degradation and stabilization of organic wastes by earthworms and its associated microorganisms is termed as vermicomposting (Senapathi, 1996). The role of earthworms right from the time it was in organic solid waste management has been well established since first highlighted by Darwin, (1881) and the technology has been @ IJTSRD | Available Online @ www.ijtsrd.com | Volume -2 | Issue -3 | Mar-Apr 2018 The main aim of this study for the reuse of organic wastes by vermicomposting method. A method is a recognised environmentally safe technology for waste reuse. It has a sustainable solid waste management. The explosive growth of human population and technological advances has produced enormous quantities of solid wastes, the management of which has become a problem of global concern. Earthworms, by their peculiar food, feeding and dered as the most efficient converters of wastes. India, being an agricultural country produces huge quantities of agricultural wastes, which can be converted into vermicompost, a nutrient rich bio fertilizer and soil conditioner. In the attempt has been made to explore the possibility of using earthworms for converting Vegetable wastes, and into vermicompost. Three epigeic well established as efficient bio and E. eugeniae-

Vermicompost, Epigeic Earthworms,
The biological degradation and stabilization of organic wastes by earthworms and its associated microorganisms is termed as vermicomposting (Senapathi, 1996). The role of earthworms right from the time it was in organic solid waste management has been well established since first highlighted by Darwin, (1881) and the technology has been improvised to process the waste to produce an efficient bio-product vermicompost (Kale Ismail, 1993 Earthworm burrows enhance aeration and porosity of soil and improve its water holding capacity (Julka and Palwar, 2005). Thus, vermicompost is an extremely homogenous, fertile material suitable for plant growth and influences vegetation growth like root, and root lengths and biomass in a better way than chemical fertilizers (Kale and Bano, 1980). Earthworms have in-house supply of enzymes such as protease, amylase, cellulose, and chitinase, which degrade complex bio molecule into simple compounds utilizable by the symbiotic gut micro flora. The earthworms speed up the composting process and transform wastes into nutrient rich castings with the help of these enzymes. Castings are good fertilizer additive for agricultural crops (Kumar, 2004 During vermicompost process, when organic matter passes through the gut of earthworms, it undergoes physical, chemical and biochemical changes by the combined effect of earthworms and microbial activities. Vermicomposting, the microbial composting of organic wastes through earthworm adequate technology for its Earthworm burrows enhance aeration and porosity of soil and improve its water holding capacity (Julka and Palwar, 2005). Thus, vermicompost is an extremely homogenous, fertile material suitable for plant growth and influences vegetation growth like root, and root lengths and biomass in a better way than chemical fertilizers (Kale and Bano, 1980). Earthworms have house supply of enzymes such as protease, amylase, cellulose, and chitinase, which degrade bio molecule into simple compounds utilizable by the symbiotic gut micro flora. The earthworms speed up the composting process and transform wastes into nutrient rich castings with the help of these enzymes. Castings are good fertilizer ultural crops (Kumar, 2004). The enzymes secreted by the earthworms alone and or in International Journal of Trend in Scientific Research and Development (IJTSRD) ISSN: 2456-6470 Page: 2495 association with gut micro flora are responsible for decomposition complex organic materials and humification of soil organic matter (Dharmalingam, 2005). It is therefore easy to speculate that vermicasts are rich in enzymes, which accelerated the mineralization rate and converted the wastes into organic fertilizer with higher nutritional value (Lakshmi praba et al., 2004).

MATERIAL AND METHODS
Collection and pre decomposition of municipal solid wastes and cow dung The biodegradable organic solid wastes were collected from Karikulam municipal solid wastes dumping site, at Kumbakonam. The wastes were chopped into small pieces and allowed to partial decomposition for 20 days. Then the waste was mixed with Cow dung in 3:1 ratio. and vermicomposting pits were used (0.75 x 0.75 x 0.75 m size) for vermiculture. 100 kg of (dry weight) of the substrate (both plant leaf litters and vegetable wastes) placed in each of the three tanks and vermin bins were inoculated with three species of earthworms with varying number (E. foetida-154; E. eugeniae-118;and P. exacavatus-124), but with similar cumulative body weight, since the limit on populations of all earthworm species, in organic wastes, seems to be related to earthworm biomass per unit of waste rather than to overall numbers (Dominguez et al.,2001). Moisture content of the substrate was adjusted to 70 to 80%. Three replicates were maintained for each species. The worms were not supplied additional food and the cultures were maintained for 62 days under maximum average temperature 30.5+0.29*c in ventilated area. Care was taken avoid light, rainfall, and natural enemies. The live weight (with full gut content) of the mature worms were measured weekly by hand sorting of the culture media and their juvenile numbers were counted after 62 days.
Vermicompost was harvested after 62 nd day from the start of bio dung composting. Vermicompost after harvested that sieved through 3mm sieve. It was subjected to chemical analysis (pH, Ec, organic carbon, nitrogen, phosphorus and potassium) to asses it nutrient status (Jackson 1973;Chopra and Kanwar, 1978). The chemical analysis of the initial substrate ( pH, N, P, K and ash ) were carried out following standard methods ( Jackson, 1973 ).

RESULTS
The physic chemical parameters of the initial, control, harvested vermicomposting prepared from organic solid wastes were analysed (Table 1, 2). The maximum temperature of the vermibed and vermibin was 26 o C in the first day at the end of the experiment (62 nd day) the control sample was recorded to have 25 o C, 23 o C, 24 o C and 24 o C were observed in the case of P. exacavatus, E. eugeniae andE. foetida worked vermibeds and vermin -bins, respectively. A decreased trend of temperature observed maybe due to the regular watering and periodic turning of the vermibeds.
Worms are sensitive to change in pH. They prefer neutral condition. The pH of the initial substrate was 7 which increased to 7.3 to the control and 7.8, 7.7, and 7.6 in P. excavatus, E. eugeniae and E. foetida vermicompost beds, respectively. The addition of cow dung as a feed for the earthworms may be responsible for the slight increase in the pH of the harvested product.
Electrical conductivity, the indicator of the concentration of soluble salts were found to be 0.64-0.74 initial sample and 1.74 in m.mhose/cm in control P. excavatus, E.eugeniae and E.foetida composts showed an increased electrical conductivity of the order of 11.70, 10.24 and 9.82m.mhos/cm respectively. The increased electrical conductivity may be due to the presence of exchangeable calcium, magnesium and potassium in casts of the worms. The nitrogen content was significantly higher in P. excavatus, E. eugeniae, E. foetida incorporated composts (1.94, 1.82, 1.26%) respectively, and compared to the control (0.92%) and initial (0.69%) samples.
The phosphorus level was found to be increased in P. excavatus and E. foetida treated wastes (2.47, 2.14 and 2.05 %) respectively in comparison with the initial (0. 224.5 and 4250.0%) samples. In E. foetida treated wastes, the micronutrient content was not found to be increased.
The volatile solids were gradually decreases during the process, which indicates the degradation of the material is completed. The total solids are rough indicators for the reduction for matter. The total solids should decrease when material degrades initiating the proper humification, which depends upon organic characteristics of feed substrate. Units-ppm-parts per million, **Ec -Electrical conductivity is measure of the relative salinity of soil or the amount of soluble salts it contains. *** Kjeldahl nitrogen -is a measure of the total percentage of nitrogen in the sample including that in the organic matter. Values on dry weight basis, average values of five samples. *Units-ppm-parts-per million, ** Ec -Electrical conductivity is measure of the relative salinity of soil or the amount of soluble salts it contains. *** Kjeldahl nitrogen -is a measure of the total percentage of nitrogen in the sample including that in the organic matter.

DISCUSSION
The amount of urban waste in India is increasing constantly and it needs to be disposed off in landfills or via incineration. However, public acceptance and the cost of these waste disposal methods and the main problems for the authorities. Fruit and vegetable waste constitutes about 70,000 tonnes per annum, which represents the significant amount of municipal solid wastes (Dominguez et al., 1997;Edwards and Bohlen, 1996). In terrestrial ecosystems, litter is the main component of detritus, which enters the decomposition subsystem and broken down by an array of decomposing organism. The litter decomposition is an important functional process of terrestrial ecosystem governing the cycling of nutrients ( Karmegam and Daniel, 1999 The phosphorus level was found to be increased in P. excavates, E. eugeniae and E. foetida treated wastes (2.24, 2.14 and 2.05 %) respectively in comparison with the initial (0.20 %) and control (1.24 %) samples.
Similarly the value of the potassium in the harvested compost obtained through the action of P. excavates, E. eugeniae and E. foetida was found to be more of the order of 2.70, 2.35 and 2.15 % respectively when compared with the control (1.28 %) and the initial organic waste (0.48%) under investigation. Graft (1971); Nijhawan and kanwarn (1952), Ramalingam (1997) and Hemalatha and Meenambal (2006) recorded similar trends of results which strongly support the present work.
Total solids are rough indicators for the reduction for matter. The total solids decrease when material degrades indicating the proper humification, which depends upon organic characteristics of feed substrate. Macro and micro (Zn, Cu, Mn and Fe) were significantly higher in vermicast is attained the required quality of manure.

CONCLUSION
From the investigation, it may be concluded that Perionyx excavates could be adjudged as the best suited worm for converting the leaf litters and vegetable waste into bio composts in terms of nutrient and physical structure. From this investigation, it appeared that suitability of plant leaf litters viz., Mango, pongamia, Polyalthia and vegetable wastes as vermiculture substrate for the species studied in descending order was P. excavates > E.eugeniae > E. foetida.